I think some people believe that they are NOT needed. Or that they claim to do something (clean & lube) but they actually do not.

I know for sure that Power Service and Marvel Mystery DO clean & lube. There is NO DOUBT about that.

The question is whether or not we NEED to add that to our fuel. Some say yes, some say no. I believe that it CAN'T hurt and it COULD help. Which makes it worth it for me. Especially since our injectors are so touchy to dirt and poor lube.